Link between political views and physiology

It is becoming more and more clear that political views are in fact not completely decided by rational considerations, as common sense would have us believe. Rather, previous studies have shown a link between emotional (i.e., largely uncontrollable) responses and position on the left/right spectrum: "those on the right are ‘distrustful of differences … fear change, dread disorder, are intolerant of nonconformity, and derogate reason’."*

A new study takes this even further, showing that there are physiological differences between people to the political left and right: "compared with individuals on the political left, individuals on the right direct more of their attention to the aversive despite displaying greater physiological responsiveness to those stimuli."

The researchers measured skin conductivity of people as they were looking at aversive images (spider on a face, maggots in a wound, crowd fighting with a man) and appetitive images (happy child, bowl of fruit, cute rabbit).

In the physiological session, participants were shown a series of 33 still images. Each image was shown once and was preceded by a fixation point that was displayed during an inter-stimulus interval. The order of slides was initially randomized and then presented in the same order to all participants. During the slide show, electrodermal activity (in the form of skin conductance readings) was collected using a pair of Ag|AgCl electrodes and standard psychophysiological equipment. Since eccrine glands release moisture as part of sympathetic nervous system activation, and since the rate of movement of electricity across the surface of the skin is a good indicator of the presence of moisture, electrodermal activity has long been accepted as a fairly direct and pure representation of sympathetic activity, making it a good measure of the psychological concepts of emotion, arousal and attention.

The skin of test subjects on the political right conducted more electricity than those on the left when presented with "aversive" images. That is, conservatives react more strongly to disturbing images.

Triangles: political right. Squares: political left.

As good researchers always should, the authors here moderate their discussion of these findings to not condemn:

Rather than using colourful adjectives, perhaps, the proper approach is simply to state that the aversive in life appears to be more physiologically and cognitively tangible to some people and they tend to gravitate to the political right.

They conclude that we can best understand political inclinations as being partly determined by something other than rational discourse, and propose a way forward:

Rather than believing those with political views opposing ours are lazily uninformed or wilfully obtuse, political tolerance could be enhanced and cultural conflict diminished if it is widely recognized that at least part of our political differences spring from subconscious physiological and cognitive variations that lead people to experience the world in fundamentally different ways and therefore to believe that fundamentally different political policies are appropriate.

Even if we recognize that people on the political right experience the world in a different way than those on the left, and that these differences are strongly influenced by genetic and physiological predispositions - perhaps prompting us to view them as pathological - and thereby fostering greater acceptance, it is in my mind by no means given what "left" and "right" means. The far left and far right have quite different meaning in different societies. In Denmark, for example, being on the far right does not imply that one is against welfare or abortion, while in the USA those go hand in hand. In other words, the Overton window can be moved, and the result will be that people who are on the far right will shift their actual political views, while still associating with the political right. What people identify as may be determined by non-rational factors to a large degree (but most likely not entirely), but where it is even possible to locate yourself is evidently affected by public discourse. We should therefore not view public outreach as futile because people anyway (mostly) can't change their minds, but as imperative to shifting what it means to be liberal and conservative.

* The rest of the quote from the paper goes "while Block & Block [53, p. 395] find that those on the right are ‘easily victimized, easily offended, indecisive, fearful, rigid, inhibited, relatively over-controlled and vulnerable’." Hell yeah!

Pleiotropy comes from the Greek πλείων pleion, meaning "more", and τρέπειν trepein, meaning "to turn, to convert". It designates the occurrence of a single gene affecting multiple traits, and is a hugely important concept in evolutionary biology.

I'm a postdoc at UC Santa Barbara.

All Many aspects of evolution interest me, but my research focus is currently on microbial evolution, adaptive radiation, speciation, fitness landscapes, epistasis, and the influence of genetic architecture on adaptation and speciation.